Republican Rep. Bill Cassidy has taken a huge lead over his Democratic opponent Sen. Mary Landrieu in Louisiana's Dec. 6 runoff election and could increase GOP Senate control to 54 seats.

The new internal poll by Magellan Strategies, done for the Cassidy campaign, shows Cassidy 16 points ahead of Landrieu and appearing to be coasting to an easy win, despite last-minute Democratic scrambling, The Hill reports.

In the midterm elections, Cassidy trailed one point behind Landrieu, 43-42 percent, with tea party candidate Rob Maness taking 14 percent of the vote. Maness now is rallying his supporters to back Cassidy, The Hill reported.

In a surprise political move, Democrats suddenly backed off their six-year opposition to construction of the controversial Keystone XL Pipeline in a bid to boost Landrieu, chair of the Senate Energy and Natural Resources Committee, in energy-rich Louisiana and indicated that the Senate will vote on a Landrieu-backed bill to build the pipeline, NPR reports.

Cassidy has sponsored legislation in the House and said in a statement that it is "easy to wonder if the Senate is only considering this because of politics. Even so, I hope the Senate and the president do the right thing and pass this legislation creating thousands of jobs," NPR reported.

Landrieu has been distancing herself from appearing too connected to unpopular President Barack Obama and the Democratic leadership, saying, "I've stood against my leadership and I've stood up to the Republicans," NPR reported.

However, National Review notes that even if the Keystone bill passes both the House and Senate, President Obama, who has opposed construction of the pipeline pending a State Department approval process, has said he will veto it.

Sen. John Hoeven, R-North Dakota, told Reuters, "If he does veto it, however, we aren't finished. We'll pass it as either part of broader energy legislation or as an amendment to another must-pass bill."

Republicans, while favoring the pipeline, have criticized what they see as Democratic political maneuvering in an attempt to support Landrieu.

Sen. John Cornyn, R-Texas, told Politico, "It seems fairly cynical to me after the election, like they’re going to fool people into thinking 'we’re for it.'"

Sen. Mitch McConnell, R-Kentucky, and the incoming Senate majority leader, said, "I hope this post-election conversion on Keystone signals Democrat cooperation on a whole host of other energy bills they have blocked, and whose passage would help to make America more energy-independent," NPR reported.

Fox News, noting that Obama has said he will hold fast on blocking Keystone, commented, "The pipeline was only put on the lame-duck Congress agenda because Louisiana Democratic Sen. Mary Landrieu pushed it on the Senate side in an apparent effort to not only boost the energy industry, but boost her own re-election bid in a tough runoff next month."

The House has scheduled a Friday vote and the Senate has set a Tuesday vote on the pipeline, The Guardian reports, noting that Landrieu believes Keystone supporters in the Senate have the 60 votes necessary for passage.